1. Field of the Disclosure
The present disclosure relates generally to integrated circuits, and more particularly to detecting failures at the integrated circuit.
2. Description of the Related Art
It is well understood that integrated circuits can operate over a wide range of temperatures and process variations. As a result, integrated circuits are generally designed to operate for worst case scenarios across all possible variations. With respect to temperature variations, transistors tend to switch more slowly at higher temperatures. In order to facilitate an understanding of various speed paths at portions of an integrated circuit, the use of arrayed diodes have been implemented whereby the current changes at the diodes is a function of temperature which can be monitored external the integrated circuit. An additional method of monitoring on-chip temperature can be accomplished though the use of ring oscillators whereby output frequency changes as a function of temperature and can be monitored external the device. However, such ring oscillators require calibration at multiple temperatures before they can be accurately used. In devices where reliability is sufficiently critical, circuits can be mirrored in order to determine that the mirrored circuits are both operating in a similar manner by monitoring the obtained results. Even with these techniques, the possibility of a failure occurring that goes undetected is possible, as is the possibility of a detected error occurring for an unknown reason. Therefore, a method and device overcoming these problems would be useful.
The use of the same reference symbols in different drawings indicates similar or identical items.